Structure and chemistry of the Dufour gland in Pristomyrmex ants (Hymenoptera, Formicidae)

Billen, J., Ito, F., Tsuji, K., Schoeters, E., Maile, R. and Morgan, E. D. 2000. Structure and chemistry of the Dufour gland in Pristomyrmex ants (Hymenoptera, Formicidae). —Acta Zoologica (Stockholm) 81 : 159–166 All individuals of the three species of Pristomyrmex studied have a Dufour gland with a conspicuous hammer‐shaped distal part, that is connected to a thin‐walled proximal reservoir through a very narrow stalk. The secretory distal part is formed by high columnar cells that are characterized by a highly folded apical wall. The lateral cell junctions apically correspond with the crenel tops, which gives individual cells a peculiar shape with a deep apical depression. The cytoplasm of the secretory cells contains a very well developed smooth endoplasmic reticulum and Golgi apparatus, numerous mitochondria and lysosomes. Histochemical analysis indicates a positive reaction for the presence of a lipid secretion in the hammer‐like part. Gas chromatographic analysis of glands of P. pungens workers reveals the secretion to be formed of a mixture of simple volatile monoterpene hydrocarbons; α–pinene, β–pinene, limonene and camphene. Similar, but species characteristic mixtures of four monoterpenes were found in Pristomyrmex brevispinosus and Pristomyrmex sp.1. Behavioural experiments did not allow a conclusive determination of the function of the gland.     

The intramandibular gland,a novel exocrine structure in ants (Insecta,Hymenoptera)

Summary A novel glandular structure is described within the mandibles of a series of representatives of the Formicidae. It consists of a variable number of secretory cells with their accompanying duct cells, located in the vicinity of the mandibular cuticle. Because of its localization inside the mandibles, we propose to designate this structure as the intramandibular gland of ants. Ultrastructural observations reveal the development of smooth endoplasmic reticulum in the glandular cells. Several electron-lucid and electron-dense inclusions occur in the cytoplasm. Until now, the function of this widespread gland among the Formicidae remains unknown.     

The basicoxal gland, a new exocrine structure in poneromorph ants (Hymenoptera, Formicidae)

The tegumental epithelium of the outer dorsolateral region in the proximal part of the coxae in the mid‐ and hindlegs of both workers and queens of the ants Odontomachus rixosus and O. simillimus is differentiated into a conspicuous and hitherto unknown exocrine gland. The glandular cells display a clear microvillar differentiation of their apical cell membrane, and are lined with the tegumental cuticle, which in this part contains crack‐like channels perpendicular to its surface, that carry the glandular secretions to the outside. Apical microvilli support the transport of substances, and contain an extension of tubular smooth endoplasmic reticulum in their centre. The function of the gland may be that of providing lubricant substances to the articulation region of the generally heavily sclerotized ponerine ant species. The gland is also found in several other ponerine and amblyoponine species, but not in the ectatommine species studied. The foreleg coxae lack a basicoxal gland in all species examined, which may be explained by the more limited articulation between the thorax and the coxae in the forelegs compared to the mid‐ and hindlegs.     

Preferred temperatures of desert honey ants (hymenoptera: formicidae)

1. 1.Preferred temperature ranges were determined for workers of 5 species of Myrmecocystus in a temperature gradient on wet sand.

2. 2.Workers of the diurnally foraging species, M. mendax Wheeler, M romainei Cole, M. depilis Forel, and M. mimicus Wheeler, were distributed between 7 and 45°C, and workers of one nocturnal species, M. mexicanus Wesmael, were distributed between 5 and 35°C.

3. 3.Mean preferred temperatures of the 5 species increased as follows: mexicanus < mendax < romainei < depilis < mimicus.

4. 4.Preferred temperatures of M. romainei and M. mexicanus were higher in the summer than in the fall.

5. 5.After 2 h in the gradient on dry sand, workers of M. romainei were distributed similarly to those on wet sand, but after 8 h on dry sand, most workers were below 12°C where the air was saturated.

Distribution and comparative morphology of the cloacal gland in ants (Hymenoptera : Formicidae)

The cloacal gland is a paired exocrine structure, which has so far been described only in the formicine species, Camponotus ephippium and Cataglyphis savignyi (Hymenoptera : Formicidae). The gland is formed by 2 clusters of bicellular units with slender duct cells, releasing the glandular secretion through the cloacal membrane. In the present work, a number of ant species, largely of the Formicinae subfamily, have been surveyed for the presence of a cloacal gland. The gland is present in nearly all formicines screened, albeit with a variable development. Cataglyphis, one of the genera with a very prominent cloacal gland, was chosen for a more detailed comparative study. At the ultrastructural level, secretory cells were observed having a well-developed smooth endoplasmic reticulum and Golgi apparatus, typical for pheromone-producing glandular cells. The gland is also present in all dolichoderines screened, but in none of the species of the Aneuretinae, Myrmeciinae, Myrmicinae, Nothomyrmeciinae, or Pseudomyrmecinae investigated. This provides tentative evidence that the cloacal gland is a synapomorphy of the Formicinae and Dolichoderinae, giving support for their hypothesized sister group relationship. Up to now, the function of the cloacal gland remains largely enigmatic.     

The antenna cleaner gland in Messor rufitarsis (hymenoptera, formicidae)

TEM and SEM analysis of the tibio-tarsal antennal cleaner in Messor rufitarsis reveals a pore region on the surface of the basitarsus. These pores are originating from a cluster of highly prismatic epidermal cells that fill the anterior hemolymph space of the leg almost completely. Within the cytoplasma of the cells, basal labyrinth, nucleus/rough endoplasmic reticulum, 'secondary lysosomes', a lot of smooth endoplasmic reticulum and distal microvilli regions can be distinguished indicating that the cells are 'class I' gland cells. Their secretion appears to be transported to the antennal cleaner apparatus via a subcuticular space and pores. It is suggested that the secretion might be used for cleaning of the antenna and/or chemical communication. SEM examination of six additional species indicates that an antennal cleaner gland might be present throughout the ants.     

Miocene ants (Hymenoptera,Formicidae) from Crimea

Ant imprints, new and previously known, from Middle Miocene deposits near Kerch (Crimean Peninsula, Russia) are described or redescribed. A new Myrmicinae species, Solenopsis atavinus sp. nov., is described based on a wingless female. A winged female similar to the earlier described Dolichoderus tauricus Dlussky, 1981 is found: due to the excellent preservation of this specimen, the new specimen and the holotype of D. tauricus are redescribed and can be reclassified as Ponerites tauricus (Dlussky, 1981), comb. nov. Oecophylla taurica sp. nov. is described based on a partly preserved imprint of a female thorax with a forewing, the venation of which allows it to be positively identified as a weaver ant. Two other species are transferred from the formal genus Camponotites to Oecophylla based on forewing venation: O. kraussei (Dlussky et Rasnitsyn, 1999), comb. nov. (Early Eocene, United States) and O. macroptera (Dlussky, 1981), comb. nov. (Middle Miocene, Stavropol, Russia). One of the studied forewing imprints is similar in venation to Paraphaenogaster microphthalmus Dlussky, 1981, described from the Middle Miocene of Vishnevaya Balka (Stavropol province, Russia) and so is attributed to this species. Dolichoderus tavridus sp. nov. is described based on a forewing.     

Catalogue of the ants (Hymenoptera, Formicidae) of Bulgaria

The present catalogue of the ants (Hymenoptera, Formicidae) of Bulgaria is made on a base of critical reconsideration of literature (covering the period from 1892 till 2009 and part of 2010) as well as on examination of the authors' and several museum's collections. A lot of data were omitted in the previous Bulgarian monograph on ants, lots of new data were recently added and many important additions and alterations were made due to taxonomic revisions of Eurasian Formicidae during the last three decades. Two new species are reported for the country [Temnothorax graecus (Forel, 1911) and Temnothorax cf. korbi (Emery, 1924)].This catalogue contains a list of 163 ant species belonging to 40 genera of 6 subfamilies now known from Bulgaria. Synonyms and information on the previously reported names in relevant publications are given. Known localities of the species are grouped by geographic regions. Maps with concrete localities or regions for each species were prepared. The conservation status of 13 ant species is given as they are included in IUCN Red List of Threatened Species and Bulgarian Biodiversity Act. In comparison with adjacent Balkan regions the ant fauna of Bulgaria is quite rich and its core is composed of South European elements.     

Karyological studies of Japanese ants (Hymenoptera,Formicidae)

The karyotypes of nine Japanese ants in three subfamilies (Ponerinae, Formicinae, and Myrmicinae) were successfully analysed by the improved squash technique. Three ponerine species had 2n=7 and n=4 (Ponera scabra), 2n=22 (Brachyponera sinensis), and 2n=28 and n=14 (Cryptopone sauteri). Four formicine species had 2n=18 and n=9 (Camponotus sp. and C. tokioensis), 2n=26 and n=13 (Camponotus japonicus), and 2n=30 and n=15 (Lasius niger). Two myrmicine species had 2n=18 and n=9 (Leptothorax congruus), and 2n=37, 38, 39, and n=17, 18, 19, 20 (Pheidole nodus). It was found that the variation of chromosome number observed in P. nodus was caused by Robertsonian type polymorphism.     

The sting bulb gland in myrmecia and Nothomyrmecia (Hymenoptera : Formicidae): A new exocrine gland in ants

A new exocrine gland has been discovered within the sting of the endemic Australian ants of the genera Myrmecia and Nothomyrmecia (Hymenoptera : Formicidae). It consists of approximately 20 secretory cells with their accompanying duct cells, located between the ducts of the venom and Dufour glands in the proximal part of ths sting bulb, hence my suggestion to designate it as the sting bulb gland. Ultrastructural examination reveals the development of both granular and smooth endoplasmic reticulum in the glandular cells, which possibly may indicate the elaboration of a rather complex secretion. Although the function of the gland remains unknown, its exclusive presence in these ants provides another argument for a closer phylogenetic relationship between both genera than is reflected by their actual classification.     

Some aspects of interrelations between ants (Hymenoptera,Formicidae) and polistine wasps (Hymenoptera,Vespidae)

Embodied, situated and enactive aspects of relationships of polistine wasps with ants are considered within the framework of the theory of autopoiesis. The idea of the embodied interaction implies specific nestbuilding and protective behavior in polistine wasps. The paper examines the adaptive role of applying ant repellent on the petiole and nest and the latitude gradient of such behavior in re-social wasp species. The situated interaction is considered in the environmental context: the mortality of Polistes gallicus (L.) colonies as a result of predatory attacks of ants Myrmica bergi Ruzsky is analyzed in the Lower Dnieper basin (Ukraine). The enactive interaction includes both spontaneous autonomous activity of its participants as a result of self-organization and specific features of the spatial structure of the prey’s population forming under the impact of the predator. The applicability of some “predator-prey” models is discussed.     

Labial gland disease in the genusFormica (Formicidae,Hymenoptera)

Summary Labial gland disease causes swelling of the labial glands in the pupal stage inFormica species. The resulting adults have enlarged thoraces and are called secretergates (Wasmann's pseudogynes). They infect the younger larvae, probably during feeding. The agent of the disease is unknown. It soon becomes non-infectious outside the labial glands. Diseased females were not seen to feed larvae. Yet their offspring contained secretergates. The discrepancy remains unexplained.     

Atypical vitellins in ponerine ants (Formicidae: Hymenoptera)

Higher hymenopteran vitellogenin/vitellins have been characterized as containing one large apoprotein. We show that in the ant subfamily Ponerinae, species in the tribes Odontomachini, Platythyrini, and Amblyoponini, also have a vitellin with this simple structure, containing a single apoprotein of 180-190kDa. Species in tribes Ponerini and Ectatommini, however, have vitellins containing multiple subunits. The size and number of the subunits varies, with differences even among species within the same genus. This is the first report of diversity in vitellogenin structure in the higher Hymenoptera. Vitellin and vitellogenin in Harpegnathos saltator (Ponerini) contain two large subunits of about 165kDa and two small subunits of about 45 and 43kDa. N-terminal sequence analysis suggests that provitellogenin is cleaved at two different sites, producing two large and two small subunits differing slightly in size. Diversity of vitellin types in Ponerini and Ectatommini is similar to that found in the more primitive tenthredinoid sawflies (Hymenoptera, Symphyta), and may indicate polyphyly in the Ponerinae. Insect vitellogenins and yolk proteins show considerably more diversity than originally believed, and the possibility of the functional significance of these differences should be considered.     

New fossil ants of the subfamily Myrmeciinae (Hymenoptera, Formicidae) from Germany

Two new fossil members of the subfamily Myrmeciinae are described: Archimyrmex wedmannae, sp. nov (Grube Messel, Germany, Middle Eocene) and Prionomyrmex wappleri, sp. nov. (Rott, Germany, Late Oligocene). Members of the genus Archimyrmex were known earlier from Eocene deposits of the United States and Argentina, and members of the genus Prionomyrmex were known from Late Eocene Baltic amber.